Preamble transmission configuration

ABSTRACT

Methods, systems, and devices for wireless communications are described. A communication device, such as a user equipment (UE) may transmit a message to a base station (e.g., a NodeB, an eNodeB (eNB), a next-generation NodeB or a giga-NodeB (either of which may be referred to as a gNB)) in wireless communications with the UE. The message may include a UE capability to append a preamble waveform to an uplink transmission to the base station. In some examples, a preamble waveform may include a Wi-Fi preamble or a new radio unlicensed (NR-U) preamble. Based on the UE capability, the base station may determine and transmit a preamble configuration to the UE, which the UE may use to generate and append a preamble waveform to another message for an uplink transmission to the base station.

CROSS REFERENCE

The present application for patent claims the benefit of U.S.Provisional Patent Application No. 62/759,959 by YERRAMALLI et al.,entitled “PREAMBLE TRANSMISSION CONFIGURATION,” filed Nov. 12, 2018,assigned to the assignee hereof, and expressly incorporated by referenceherein.

BACKGROUND

The following relates generally to wireless communications, and morespecifically to preamble transmission configuration.

Wireless communications systems are widely deployed to provide varioustypes of communication content such as voice, video, packet data,messaging, broadcast, and so on. These systems may be capable ofsupporting communication with multiple users by sharing the availablesystem resources (e.g., time, frequency, and power). Examples of suchmultiple-access systems include fourth generation (4G) systems such asLong Term Evolution (LTE) systems, LTE-Advanced (LTE-A) systems, orLTE-A Pro systems, and fifth generation (5G) systems which may bereferred to as New Radio (NR) systems. These systems may employtechnologies such as code division multiple access (CDMA), time divisionmultiple access (TDMA), frequency division multiple access (FDMA),orthogonal frequency division multiple access (OFDMA), or discreteFourier transform spread orthogonal frequency division multiplexing(DFT-S-OFDM).

A wireless multiple-access communications system may include a number ofbase stations or network access nodes, each simultaneously supportingcommunication for multiple communication devices, which may be otherwiseknown as user equipment (UE). In some wireless communications systems,base stations and UEs may communicate using different radio accesstechnologies. Conventional interference avoidance techniques to supportcoexistence across different radio access technologies may beineffective or deficient.

SUMMARY

The described techniques relate to improved methods, systems, devices,and apparatuses that support preamble transmission configuration. Someexamples of wireless communications systems may support multipledifferent radio access technologies including licensed and unlicensedradio frequency spectrum bands. For example, a user equipment (UE) maysupport fourth generation (4G) systems such as Long Term Evolution (LTE)systems, LTE-Advanced (LTE-A) systems, and fifth generation (5G) systemswhich may be referred to as New Radio (NR) systems. The UE mayadditionally, or alternatively, support wireless local area networks(WLAN), such as Wi-Fi (i.e., Institute of Electrical and ElectronicsEngineers (IEEE) 802.11). Accordingly, a UE may be capable of supportingat least one or a combination of the different radio accesstechnologies.

In some examples of a wireless communications system, a UE supportingone radio access technology may have a negative impact (e.g.,interference) on other UEs supporting another radio access technology.For example, a UE supporting 4G, 5G radio access technologies may posecontention-based challenges to other UEs supporting Wi-Fi radio accesstechnologies. To support coexistence between multiple different radioaccess technologies, a UE may support a preamble transmission, such as aWi-Fi preamble or a new radio unlicensed (NR-U) preamble, and morespecifically the UE may support a preamble transmission in accordancewith a preamble configuration. For example, a UE may operate accordingto 4G, 5G radio access technologies. In this example, the UE may becapable of transmitting a Wi-Fi preamble without actually supportingWi-Fi radio access technologies. Therefore, the UE supporting 4G, 5Gradio access technologies may append a Wi-Fi preamble to NR-Ucommunications. As a result, the UE may support coexistence between 4G,5G radio access technologies enabled UEs and Wi-Fi radio accesstechnologies enabled UEs. In addition, by appending a Wi-Fi preamble toNR-U communications, the UE may provide a fair channel contention forother UEs (e.g., Wi-Fi devices) attempting to coexist with UEs (e.g.,4G, 5G devices) on a same channel.

A method of wireless communications at a UE is described. The method mayinclude transmitting a first message to a base station, the firstmessage indicating a UE capability to append a preamble waveform to anuplink transmission to the base station, where the preamble waveform isdirected at a device, appending the preamble waveform to a secondmessage for transmission to the base station based at least in part onthe indicated UE capability, and transmitting the second message withthe appended preamble waveform.

An apparatus for wireless communications is described. The apparatus mayinclude a processor, memory in electronic communication with theprocessor, and instructions stored in the memory. The instructions maybe executable by the processor to cause the apparatus to transmit afirst message to a base station, the first message indicating anapparatus capability to append a preamble waveform to an uplinktransmission to the base station, where the preamble waveform isdirected at a device, append the preamble waveform to a second messagefor transmission to the base station based on the indicated apparatuscapability, and transmit the second message with the appended preamblewaveform.

Another apparatus for wireless communications is described. Theapparatus may include means for transmitting a first message to a basestation, the first message indicating an apparatus capability to appenda preamble waveform to an uplink transmission to the base station, wherethe preamble waveform is directed at a device, appending the preamblewaveform to a second message for transmission to the base station basedon the indicated apparatus capability, and transmitting the secondmessage with the appended preamble waveform.

A non-transitory computer-readable medium storing code for wirelesscommunications at a UE is described. The code may include instructionsexecutable by a processor to transmit a first message to a base station,the first message indicating a UE capability to append a preamblewaveform to an uplink transmission to the base station, where thepreamble waveform is directed at a device, append the preamble waveformto a second message for transmission to the base station based on theindicated UE capability, and transmit the second message with theappended preamble waveform.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for including in the firstmessage an indication of a version of the preamble waveform, where thepreamble waveform appended to the second message may be of the indicatedversion.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for including in the firstmessage an indication that the UE dynamically selects a version of thepreamble waveform, where appending the preamble waveform to the secondmessage includes dynamically selecting the version of the preamblewaveform.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for including in the firstmessage an indication of a length of the preamble waveform.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the preamble waveformcomprises a Wi-Fi preamble or a new radio unlicensed (NR-U) preamble.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for including in the Wi-Fipreamble an indication of a device type of the UE.

A method of wireless communications at a base station is described. Themethod may include receiving a first message from a UE, the firstmessage indicating a UE capability to append a preamble waveform to anuplink transmission to the base station, where the preamble waveform isdirected at a device; and receiving a second message with the appendedpreamble waveform.

An apparatus for wireless communications is described. The apparatus mayinclude a processor, memory in electronic communication with theprocessor, and instructions stored in the memory. The instructions maybe executable by the processor to cause the apparatus to receive a firstmessage from a UE, the first message indicating a UE capability toappend a preamble waveform to an uplink transmission to the apparatus,where the preamble waveform is directed at a device other than theapparatus; and receive a second message with the appended preamblewaveform.

Another apparatus for wireless communications is described. Theapparatus may include means for receiving a first message from a UE, thefirst message indicating a UE capability to append a preamble waveformto an uplink transmission to the apparatus, where the preamble waveformis directed at a device other than the apparatus; and receiving a secondmessage with the appended preamble waveform.

A non-transitory computer-readable medium storing code for wirelesscommunications at a base station is described. The code may includeinstructions executable by a processor to receive a first message from aUE, the first message indicating a UE capability to append a preamblewaveform to an uplink transmission to the base station, where thepreamble waveform is directed at a device; and receive a second messagewith the appended preamble waveform.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the first message comprisesan indication of a version of the preamble waveform, where the preamblewaveform appended to the second message is of the indicated version.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the first message comprisesan indication that the UE dynamically selects a version of the preamblewaveform.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the first message comprisesan indication of a length of the preamble waveform.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the preamble waveformcomprises a Wi-Fi preamble or a new radio unlicensed (NR-U) preamble.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the Wi-Fi preamble comprisesan indication of a device type of the UE.

A method of wireless communications at a UE is described. The method mayinclude receiving from a base station, a preamble configuration foruplink transmissions, generating, based on the preamble configuration, apreamble waveform directed to a device, and performing an uplinktransmission to the base station, where the preamble waveform isappended to a beginning of the uplink transmission based on the preambleconfiguration.

An apparatus for wireless communications is described. The apparatus mayinclude a processor, memory in electronic communication with theprocessor, and instructions stored in the memory. The instructions maybe executable by the processor to cause the apparatus to receive from abase station, a preamble configuration for uplink transmissions,generate, based on the preamble configuration, a preamble waveformdirected to a device, and perform an uplink transmission to the basestation, where the preamble waveform is appended to a beginning of theuplink transmission based on the preamble configuration.

Another apparatus for wireless communications is described. Theapparatus may include means for receiving from a base station, apreamble configuration for uplink transmissions, generating, based onthe preamble configuration, a preamble waveform directed to a device,and performing an uplink transmission to the base station, where thepreamble waveform is appended to a beginning of the uplink transmissionbased on the preamble configuration.

A non-transitory computer-readable medium storing code for wirelesscommunications at a UE is described. The code may include instructionsexecutable by a processor to receive from a base station, a preambleconfiguration for uplink transmissions, generate, based on the preambleconfiguration, a preamble waveform directed to a device, and perform anuplink transmission to the base station, where the preamble waveform isappended to a beginning of the uplink transmission based on the preambleconfiguration.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for determining, based onthe preamble configuration, whether the UE may be permitted to appendthe preamble waveform to the uplink transmission, where performing theuplink transmission to the base station may be based on thedetermination.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for determining, based onthe preamble configuration, a format of the preamble waveform, wheregenerating the preamble waveform may be based on the determined format.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, determining the format of thepreamble waveform is further based at least in part on a band of theuplink transmission.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for determining, based onthe preamble configuration, a time at which the UE may be permitted totransmit the preamble waveform, where generating the preamble waveformmay be based on the determined time.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the preamble configuration isreceived in a downlink control information block including an indicationof the time at which the UE is permitted to transmit the preamblewaveform.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, determining the time at whichthe UE is permitted to transmit the preamble waveform is further basedat least in part on one or more of: an uplink channel configuration ofthe UE or a bandwidth of the uplink transmission.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for receiving an indicationof a transmission opportunity of the base station; where determining thetime at which the UE may be permitted to transmit the preamble waveformmay be further based at least in part on the transmission opportunity ofthe base station.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for receiving an indicationof a duration field value from the base station; where generating thepreamble waveform includes signaling the indicated duration field valuein the preamble waveform.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for receiving an indicationthat a transmit power setting and a beamforming matrix configured forthe uplink transmission may be applicable to the preamble waveform;where the uplink transmission includes transmitting the preamblewaveform according to the transmit power setting and using thebeamforming matrix.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for determining, based onthe preamble configuration, an energy detection threshold to use foraccess to a channel, and performing a channel access procedure based onthe determined energy detection threshold.

A method of wireless communications at a base station is described. Themethod may include transmitting to a UE, a preamble configurationincluding an indication to append a preamble waveform to an uplinktransmission, where the preamble waveform is directed at a device andreceiving the uplink transmission from the UE, where the preamblewaveform is appended to a beginning of the uplink transmission based onthe preamble configuration.

An apparatus for wireless communications is described. The apparatus mayinclude a processor, memory in electronic communication with theprocessor, and instructions stored in the memory. The instructions maybe executable by the processor to cause the apparatus to transmit to aUE, a preamble configuration including an indication to append apreamble waveform to an uplink transmission, where the preamble waveformis directed at a device other than the apparatus and receive the uplinktransmission from the UE, where the preamble waveform is appended to abeginning of the uplink transmission based on the preambleconfiguration.

Another apparatus for wireless communications is described. Theapparatus may include means for transmitting to a UE, a preambleconfiguration including an indication to append a preamble waveform toan uplink transmission, where the preamble waveform is directed at adevice other than the apparatus and receiving the uplink transmissionfrom the UE, where the preamble waveform is appended to a beginning ofthe uplink transmission based on the preamble configuration.

A non-transitory computer-readable medium storing code for wirelesscommunications at a base station is described. The code may includeinstructions executable by a processor to transmit to a UE, a preambleconfiguration including an indication to append a preamble waveform toan uplink transmission, where the preamble waveform is directed at adevice and receive the uplink transmission from the UE, where thepreamble waveform is appended to a beginning of the uplink transmissionbased on the preamble configuration.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for including in thepreamble configuration an indication that the UE may be permitted toappend the preamble waveform to the uplink transmission.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for including in thepreamble configuration an indication of a format of the preamblewaveform.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the format of the preamblewaveform is further based at least in part on a band of the uplinktransmission.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for including in thepreamble configuration an indication of a time at which the UE may bepermitted to transmit the preamble waveform.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the preamble configuration istransmitted in a downlink control information block including anindication of the time at which the UE is permitted to transmit thepreamble waveform.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the time at which the UE ispermitted to transmit the preamble waveform is further based at least inpart on one or more of: an uplink channel configuration of the UE or abandwidth of the uplink transmission.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for transmitting anindication of a transmission opportunity of the base station to the UE;where the time at which the UE may be permitted to transmit the preamblewaveform may be further based at least in part on the transmissionopportunity of the base station.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for transmitting anindication of a duration field value to the UE.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for transmitting anindication that a transmit power setting and a beamforming matrixconfigured for the uplink transmission may be applicable to the preamblewaveform, where the uplink transmission includes receiving the preamblewaveform according to the transmit power setting and using thebeamforming matrix.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for determining, based onthe preamble configuration, an energy detection threshold to use foraccess to a channel, and performing a channel access procedure based onthe determined energy detection threshold.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1 and 2 illustrates examples of wireless communications systemsthat supports preamble transmission configuration in accordance withaspects of the present disclosure.

FIG. 3 illustrates an example of a process flow that supports preambletransmission configuration in accordance with aspects of the presentdisclosure.

FIGS. 4 and 5 show block diagrams of devices that support preambletransmission configuration in accordance with aspects of the presentdisclosure.

FIG. 6 shows a block diagram of a communications manager that supportspreamble transmission configuration in accordance with aspects of thepresent disclosure.

FIG. 7 shows a diagram of a system including a device that supportspreamble transmission configuration in accordance with aspects of thepresent disclosure.

FIGS. 8 and 9 show block diagrams of devices that support preambletransmission configuration in accordance with aspects of the presentdisclosure.

FIG. 10 shows a block diagram of a communications manager that supportspreamble transmission configuration in accordance with aspects of thepresent disclosure.

FIG. 11 shows a diagram of a system including a device that supportspreamble transmission configuration in accordance with aspects of thepresent disclosure.

FIGS. 12 through 15 show flowcharts illustrating methods that supportpreamble transmission configuration in accordance with aspects of thepresent disclosure.

DETAILED DESCRIPTION

Some examples of wireless communications systems may support multipledifferent radio access technologies including licensed and unlicensedradio frequency spectrum bands. For example, a communication device maysupport fourth generation (4G) systems such as Long Term Evolution (LTE)systems, LTE-Advanced (LTE-A) systems, or LTE-A Pro systems, and fifthgeneration (5G) New Radio (NR) systems. The communication device mayadditionally, or alternatively, support wireless local area networks(WLAN), such as Wi-Fi (i.e., Institute of Electrical and ElectronicsEngineers (IEEE) 802.11). Accordingly, the communication device may becapable of supporting at least one or a combination of the differentradio access technologies.

A user equipment (UE) may have capability to operate in both licensedand unlicensed radio frequency spectrum bands. For example, a UE mayoperate according to 4G, 5G radio access technologies, as well asaccording to Wi-Fi radio access technologies. Although these differentradio access technologies may benefit the UE, for example, in terms ofefficiency and latency, there may be a negative impact (e.g.,interference) on a wireless communications system. For example, a UEsupporting 4G, 5G radio access technologies may pose contention-basedchallenges to other UEs supporting Wi-Fi radio access technologies. Tosupport coexistence between 4G, 5G radio access technologies, as well asWi-Fi radio access technologies, a UE may support a preambletransmission, such as a Wi-Fi preamble or a new radio unlicensed (NR-U)preamble.

By way of example, a UE may operate according to 4G, 5G radio accesstechnologies without supporting Wi-Fi radio access technologies. In thisexample, the UE may be capable of transmitting a Wi-Fi preamble withoutactually supporting Wi-Fi radio access technologies. That is, the UEsupporting 4G, 5G radio access technologies may append a Wi-Fi preambleto NR-U communications. As a result, the UE may support coexistencebetween multiple different radio access technologies. For example, theUE may facilitate an effective channel contention for other UEs (e.g.,Wi-Fi devices) attempting to coexist with UEs (e.g., 4G, 5G devices) ona same channel.

To further support coexistence between 4G, 5G radio access technologies,as well as Wi-Fi radio access technologies, a UE may support a preambletransmission in accordance with a preamble configuration. For example, aUE may transmit a message to a base station in wireless communicationswith the UE. The message may indicate a UE capability to append apreamble waveform to an uplink transmission to the base station. Thebase station may generate a preamble configuration based on the UEcapability. The preamble configuration may include, but is not limitedto, a format of the preamble waveform, a time at which the UE ispermitted to transmit the preamble waveform, a transmit power settingand a beamforming matrix configured applicable to the preamble waveform,among others. Upon receiving the preamble configuration from the basestation, the UE may generate, based on the preamble configuration, apreamble waveform and append the preamble waveform to an uplinktransmission to the base station.

Aspects of the disclosure are initially described in the context of awireless communications system. Aspects of the disclosure are thenillustrated by and described with reference to a process flow. Aspectsof the disclosure are further illustrated by and described withreference to apparatus diagrams, system diagrams, and flowcharts thatrelate to preamble transmission configuration.

FIG. 1 illustrates an example of a wireless communications system 100that supports preamble transmission configuration in accordance withaspects of the present disclosure. The wireless communications system100 includes base stations 105, UEs 115, and a core network 130. In someexamples, the wireless communications system 100 may be a Long TermEvolution (LTE) network, an LTE-Advanced (LTE-A) network, an LTE-A Pronetwork, or a New Radio (NR) network. In some cases, wirelesscommunications system 100 may support enhanced broadband communications,ultra-reliable (e.g., mission critical) communications, low latencycommunications, or communications with low-cost and low-complexitydevices.

Base stations 105 may wirelessly communicate with UEs 115 via one ormore base station antennas. Base stations 105 described herein mayinclude or may be referred to by those skilled in the art as a basetransceiver station, a radio base station, an access point, a radiotransceiver, a NodeB, an eNodeB (eNB), a next-generation NodeB orgiga-NodeB (either of which may be referred to as a gNB), a Home NodeB,a Home eNodeB, or some other suitable terminology. Wirelesscommunications system 100 may include base stations 105 of differenttypes (e.g., macro or small cell base stations). The UEs 115 describedherein may be able to communicate with various types of base stations105 and network equipment including macro eNBs, small cell eNBs, gNBs,relay base stations, and the like.

Each base station 105 may be associated with a particular geographiccoverage area 110 in which communications with various UEs 115 issupported. Each base station 105 may provide communication coverage fora respective geographic coverage area 110 via communication links 125,and communication links 125 between a base station 105 and a UE 115 mayutilize one or more carriers. Communication links 125 shown in wirelesscommunications system 100 may include uplink transmissions from a UE 115to a base station 105, or downlink transmissions from a base station 105to a UE 115. Downlink transmissions may also be called forward linktransmissions while uplink transmissions may also be called reverse linktransmissions.

The geographic coverage area 110 for a base station 105 may be dividedinto sectors making up a portion of the geographic coverage area 110,and each sector may be associated with a cell. For example, each basestation 105 may provide communication coverage for a macro cell, a smallcell, a hot spot, or other types of cells, or various combinationsthereof. In some examples, a base station 105 may be movable andtherefore provide communication coverage for a moving geographiccoverage area 110. In some examples, different geographic coverage areas110 associated with different technologies may overlap, and overlappinggeographic coverage areas 110 associated with different technologies maybe supported by the same base station 105 or by different base stations105. The wireless communications system 100 may include, for example, aheterogeneous LTE/LTE-A/LTE-A Pro or NR network in which different typesof base stations 105 provide coverage for various geographic coverageareas 110.

The term “cell” refers to a logical communication entity used forcommunication with a base station 105 (e.g., over a carrier), and may beassociated with an identifier for distinguishing neighboring cells(e.g., a physical cell identifier (PCID), a virtual cell identifier(VCID)) operating via the same or a different carrier. In some examples,a carrier may support multiple cells, and different cells may beconfigured according to different protocol types (e.g., machine-typecommunication (MTC), narrowband Internet-of-Things (NB-IoT), enhancedmobile broadband (eMBB), or others) that may provide access fordifferent types of devices. In some cases, the term “cell” may refer toa portion of a geographic coverage area 110 (e.g., a sector) over whichthe logical entity operates.

UEs 115 may be dispersed throughout the wireless communications system100, and each UE 115 may be stationary or mobile. A UE 115 may also bereferred to as a mobile device, a wireless device, a remote device, ahandheld device, or a subscriber device, or some other suitableterminology, where the “device” may also be referred to as a unit, astation, a terminal, or a client. A UE 115 may also be a personalelectronic device such as a cellular phone, a personal digital assistant(PDA), a tablet computer, a laptop computer, or a personal computer. Insome examples, a UE 115 may also refer to a wireless local loop (WLL)station, an Internet of Things (IoT) device, an Internet of Everything(IoE) device, or an MTC device, or the like, which may be implemented invarious articles such as appliances, vehicles, meters, or the like.

Some UEs 115, such as MTC or IoT devices, may be low cost or lowcomplexity devices, and may provide for automated communication betweenmachines (e.g., via Machine-to-Machine (M2M) communication). M2Mcommunication or MTC may refer to data communication technologies thatallow devices to communicate with one another or a base station 105without human intervention. In some examples, M2M communication or MTCmay include communications from devices that integrate sensors or metersto measure or capture information and relay that information to acentral server or application program that can make use of theinformation or present the information to humans interacting with theprogram or application. Some UEs 115 may be designed to collectinformation or enable automated behavior of machines. Examples ofapplications for MTC devices include smart metering, inventorymonitoring, water level monitoring, equipment monitoring, healthcaremonitoring, wildlife monitoring, weather and geological eventmonitoring, fleet management and tracking, remote security sensing,physical access control, and transaction-based business charging.

Some UEs 115 may be configured to employ operating modes that reducepower consumption, such as half-duplex communications (e.g., a mode thatsupports one-way communication via transmission or reception, but nottransmission and reception simultaneously). In some examples,half-duplex communications may be performed at a reduced peak rate.Other power conservation techniques for UEs 115 include entering a powersaving “deep sleep” mode when not engaging in active communications, oroperating over a limited bandwidth (e.g., according to narrowbandcommunications). In some cases, UEs 115 may be designed to supportcritical functions (e.g., mission critical functions), and a wirelesscommunications system 100 may be configured to provide ultra-reliablecommunications for these functions.

In some cases, a UE 115 may also be able to communicate directly withother UEs 115 (e.g., using a peer-to-peer (P2P) or device-to-device(D2D) protocol). One or more of a group of UEs 115 utilizing D2Dcommunications may be within the geographic coverage area 110 of a basestation 105. Other UEs 115 in such a group may be outside the geographiccoverage area 110 of a base station 105, or be otherwise unable toreceive transmissions from a base station 105. In some cases, groups ofUEs 115 communicating via D2D communications may utilize a one-to-many(1:M) system in which each UE 115 transmits to every other UE 115 in thegroup. In some cases, a base station 105 facilitates the scheduling ofresources for D2D communications. In other cases, D2D communications arecarried out between UEs 115 without the involvement of a base station105.

Base stations 105 may communicate with the core network 130 and with oneanother. For example, base stations 105 may interface with the corenetwork 130 through backhaul links 132 (e.g., via an S1, N2, N3, orother interface). Base stations 105 may communicate with one anotherover backhaul links 134 (e.g., via an X2, Xn, or other interface) eitherdirectly (e.g., directly between base stations 105) or indirectly (e.g.,via core network 130). The core network 130 may provide userauthentication, access authorization, tracking, Internet Protocol (IP)connectivity, and other access, routing, or mobility functions. The corenetwork 130 may be an evolved packet core (EPC), which may include atleast one mobility management entity (MME), at least one serving gateway(S-GW), and at least one Packet Data Network (PDN) gateway (P-GW). TheMME may manage non-access stratum (e.g., control plane) functions suchas mobility, authentication, and bearer management for UEs 115 served bybase stations 105 associated with the EPC. User IP packets may betransferred through the S-GW, which itself may be connected to the P-GW.The P-GW may provide IP address allocation as well as other functions.The P-GW may be connected to the network operators IP services. Theoperators IP services may include access to the Internet, Intranet(s),an IP Multimedia Subsystem (IMS), or a Packet-Switched (PS) StreamingService.

At least some of the network devices, such as a base station 105, mayinclude subcomponents such as an access network entity, which may be anexample of an access node controller (ANC). Each access network entitymay communicate with UEs 115 through a number of other access networktransmission entities, which may be referred to as a radio head, a smartradio head, or a transmission/reception point (TRP). In someconfigurations, various functions of each access network entity or basestation 105 may be distributed across various network devices (e.g.,radio heads and access network controllers) or consolidated into asingle network device (e.g., a base station 105).

Wireless communications system 100 may operate using one or morefrequency bands, for example, in the range of 300 megahertz (MHz) to 300gigahertz (GHz). Generally, the region from 300 MHz to 3 GHz is known asthe ultra-high frequency (UHF) region or decimeter band, since thewavelengths range from approximately one decimeter to one meter inlength. UHF waves may be blocked or redirected by buildings andenvironmental features. However, the waves may penetrate structuressufficiently for a macro cell to provide service to UEs 115 locatedindoors. Transmission of UHF waves may be associated with smallerantennas and shorter range (e.g., less than 100 km) compared totransmission using the smaller frequencies and longer waves of the highfrequency (HF) or very high frequency (VHF) portion of the spectrumbelow 300 MHz. The wireless communications system 100 may also operatein a super high frequency (SHF) region using frequency bands from 3 GHzto 30 GHz, also known as the centimeter band. The SHF region includesbands such as the 5 GHz industrial, scientific, and medical (ISM) bands,which may be used opportunistically by devices that may be capable oftolerating interference from other users.

Wireless communications system 100 may also operate in an extremely highfrequency (EHF) region of the spectrum (e.g., from 30 GHz to 300 GHz),also known as the millimeter band. In some examples, wirelesscommunications system 100 may support millimeter wave (mmW)communications between UEs 115 and base stations 105, and EHF antennasof the respective devices may be even smaller and more closely spacedthan UHF antennas. In some cases, this may facilitate use of antennaarrays within a UE 115. However, the propagation of EHF transmissionsmay be subject to even greater atmospheric attenuation and shorter rangethan SHF or UHF transmissions. Techniques disclosed herein may beemployed across transmissions that use one or more different frequencyregions, and designated use of bands across these frequency regions maydiffer by country or regulating body.

In some cases, the wireless communications system 100 may utilize bothlicensed and unlicensed radio frequency spectrum bands. For example,wireless communications system 100 may employ License Assisted Access(LAA), LTE-Unlicensed (LTE-U) radio access technology, or NR technologyin an unlicensed band such as the 5 GHz ISM band. When operating inunlicensed radio frequency spectrum bands, wireless devices such as basestations 105 and UEs 115 may employ listen-before-talk (LBT) proceduresto ensure a frequency channel is clear before transmitting data. In somecases, operations in unlicensed bands may be based on a carrieraggregation configuration in conjunction with component carriersoperating in a licensed band (e.g., LAA). Operations in unlicensedspectrum may include downlink transmissions, uplink transmissions,peer-to-peer transmissions, or a combination of these. Duplexing inunlicensed spectrum may be based on frequency division duplexing (FDD),time division duplexing (TDD), or a combination of both.

In some examples, base station 105 or UE 115 may be equipped withmultiple antennas, which may be used to employ techniques such astransmit diversity, receive diversity, multiple-input multiple-output(MIMO) communications, or beamforming. For example, wirelesscommunications system 100 may use a transmission scheme between atransmitting device (e.g., a base station 105) and a receiving device(e.g., a UE 115), where the transmitting device is equipped withmultiple antennas and the receiving device is equipped with one or moreantennas. MIMO communications may employ multipath signal propagation toincrease the spectral efficiency by transmitting or receiving multiplesignals via different spatial layers, which may be referred to asspatial multiplexing. The multiple signals may, for example, betransmitted by the transmitting device via different antennas ordifferent combinations of antennas. Likewise, the multiple signals maybe received by the receiving device via different antennas or differentcombinations of antennas. Each of the multiple signals may be referredto as a separate spatial stream, and may carry bits associated with thesame data stream (e.g., the same codeword) or different data streams.Different spatial layers may be associated with different antenna portsused for channel measurement and reporting. MIMO techniques includesingle-user MIMO (SU-MIMO) where multiple spatial layers are transmittedto the same receiving device, and multiple-user MIMO (MU-MIMO) wheremultiple spatial layers are transmitted to multiple devices.

Beamforming, which may also be referred to as spatial filtering,directional transmission, or directional reception, is a signalprocessing technique that may be used at a transmitting device or areceiving device (e.g., a base station 105 or a UE 115) to shape orsteer an antenna beam (e.g., a transmit beam or receive beam) along aspatial path between the transmitting device and the receiving device.Beamforming may be achieved by combining the signals communicated viaantenna elements of an antenna array such that signals propagating atparticular orientations with respect to an antenna array experienceconstructive interference while others experience destructiveinterference. The adjustment of signals communicated via the antennaelements may include a transmitting device or a receiving deviceapplying certain amplitude and phase offsets to signals carried via eachof the antenna elements associated with the device. The adjustmentsassociated with each of the antenna elements may be defined by abeamforming weight set associated with a particular orientation (e.g.,with respect to the antenna array of the transmitting device orreceiving device, or with respect to some other orientation).

In one example, a base station 105 may use multiple antennas or antennaarrays to conduct beamforming operations for directional communicationswith a UE 115. For instance, some signals (e.g., synchronizationsignals, reference signals, beam selection signals, or other controlsignals) may be transmitted by a base station 105 multiple times indifferent directions, which may include a signal being transmittedaccording to different beamforming weight sets associated with differentdirections of transmission. Transmissions in different beam directionsmay be used to identify (e.g., by the base station 105 or a receivingdevice, such as a UE 115) a beam direction for subsequent transmissionand/or reception by the base station 105.

Some signals, such as data signals associated with a particularreceiving device, may be transmitted by a base station 105 in a singlebeam direction (e.g., a direction associated with the receiving device,such as a UE 115). In some examples, the beam direction associated withtransmissions along a single beam direction may be determined based atleast in part on a signal that was transmitted in different beamdirections. For example, a UE 115 may receive one or more of the signalstransmitted by the base station 105 in different directions, and the UE115 may report to the base station 105 an indication of the signal itreceived with a highest signal quality, or an otherwise acceptablesignal quality. Although these techniques are described with referenceto signals transmitted in one or more directions by a base station 105,a UE 115 may employ similar techniques for transmitting signals multipletimes in different directions (e.g., for identifying a beam directionfor subsequent transmission or reception by the UE 115), or transmittinga signal in a single direction (e.g., for transmitting data to areceiving device).

A receiving device (e.g., a UE 115, which may be an example of a mmWreceiving device) may try multiple receive beams when receiving varioussignals from the base station 105, such as synchronization signals,reference signals, beam selection signals, or other control signals. Forexample, a receiving device may try multiple receive directions byreceiving via different antenna subarrays, by processing receivedsignals according to different antenna subarrays, by receiving accordingto different receive beamforming weight sets applied to signals receivedat a plurality of antenna elements of an antenna array, or by processingreceived signals according to different receive beamforming weight setsapplied to signals received at a plurality of antenna elements of anantenna array, any of which may be referred to as “listening” accordingto different receive beams or receive directions. In some examples, areceiving device may use a single receive beam to receive along a singlebeam direction (e.g., when receiving a data signal). The single receivebeam may be aligned in a beam direction determined based at least inpart on listening according to different receive beam directions (e.g.,a beam direction determined to have a highest signal strength, highestsignal-to-noise ratio, or otherwise acceptable signal quality based atleast in part on listening according to multiple beam directions).

In some cases, the antennas of a base station 105 or UE 115 may belocated within one or more antenna arrays, which may support MIMOoperations, or transmit or receive beamforming. For example, one or morebase station antennas or antenna arrays may be co-located at an antennaassembly, such as an antenna tower. In some cases, antennas or antennaarrays associated with a base station 105 may be located in diversegeographic locations. A base station 105 may have an antenna array witha number of rows and columns of antenna ports that the base station 105may use to support beamforming of communications with a UE 115.Likewise, a UE 115 may have one or more antenna arrays that may supportvarious MIMO or beamforming operations.

In some cases, wireless communications system 100 may be a packet-basednetwork that operate according to a layered protocol stack. In the userplane, communications at the bearer or Packet Data Convergence Protocol(PDCP) layer may be IP-based. A Radio Link Control (RLC) layer mayperform packet segmentation and reassembly to communicate over logicalchannels. A Medium Access Control (MAC) layer may perform priorityhandling and multiplexing of logical channels into transport channels.The MAC layer may also use hybrid automatic repeat request (HARQ) toprovide retransmission at the MAC layer to improve link efficiency. Inthe control plane, the Radio Resource Control (RRC) protocol layer mayprovide establishment, configuration, and maintenance of an RRCconnection between a UE 115 and a base station 105 or core network 130supporting radio bearers for user plane data. At the Physical layer,transport channels may be mapped to physical channels.

In some cases, UEs 115 and base stations 105 may support retransmissionsof data to increase the likelihood that data is received successfully.HARQ feedback is one technique of increasing the likelihood that data isreceived correctly over a communication link 125. HARQ may include acombination of error detection (e.g., using a cyclic redundancy check(CRC)), forward error correction (FEC), and retransmission (e.g.,automatic repeat request (ARQ)). HARQ may improve throughput at the MAClayer in poor radio conditions (e.g., signal-to-noise conditions). Insome cases, a wireless device may support same-slot HARQ feedback, wherethe device may provide HARQ feedback in a specific slot for datareceived in a previous symbol in the slot. In other cases, the devicemay provide HARQ feedback in a subsequent slot, or according to someother time interval.

Time intervals in LTE or NR may be expressed in multiples of a basictime unit, which may, for example, refer to a sampling period ofT_(s)=1/30,720,000 seconds. Time intervals of a communications resourcemay be organized according to radio frames each having a duration of 10milliseconds (ms), where the frame period may be expressed asT_(f)=307,200 T_(s). The radio frames may be identified by a systemframe number (SFN) ranging from 0 to 1023. Each frame may include 10subframes numbered from 0 to 9, and each subframe may have a duration of1 ms. A subframe may be further divided into 2 slots each having aduration of 0.5 ms, and each slot may contain 6 or 7 modulation symbolperiods (e.g., depending on the length of the cyclic prefix prepended toeach symbol period). Excluding the cyclic prefix, each symbol period maycontain 2048 sampling periods. In some cases, a subframe may be thesmallest scheduling unit of the wireless communications system 100, andmay be referred to as a transmission time interval (TTI). In othercases, a smallest scheduling unit of the wireless communications system100 may be shorter than a subframe or may be dynamically selected (e.g.,in bursts of shortened TTIs (sTTIs) or in selected component carriersusing sTTIs). In some examples of the wireless communications system100, a slot may further be divided into multiple mini-slots containingone or more symbols. In some instances, a symbol of a mini-slot or amini-slot may be the smallest unit of scheduling. Each symbol may varyin duration depending on the subcarrier spacing or frequency band ofoperation, for example. Further, some wireless communications systemsmay implement slot aggregation in which multiple slots or mini-slots areaggregated together and used for communication between a UE 115 and abase station 105.

The term “carrier” refers to a set of radio frequency spectrum resourceshaving a defined physical layer structure for supporting communicationsover a communication link 125. For example, a carrier of a communicationlink 125 may include a portion of a radio frequency spectrum band thatis operated according to physical layer channels for a given radioaccess technology. Each physical layer channel may carry user data,control information, or other signaling. A carrier may be associatedwith a pre-defined frequency channel (e.g., an evolved universal mobiletelecommunication system terrestrial radio access (E-UTRA) absoluteradio frequency channel number (EARFCN)), and may be positionedaccording to a channel raster for discovery by UEs 115. Carriers may bedownlink or uplink (e.g., in an FDD mode), or be configured to carrydownlink and uplink communications (e.g., in a TDD mode). In someexamples, signal waveforms transmitted over a carrier may be made up ofmultiple sub-carriers (e.g., using multi-carrier modulation (MCM)techniques such as orthogonal frequency division multiplexing (OFDM) ordiscrete Fourier transform spread OFDM (DFT-S-OFDM)).

The organizational structure of the carriers may be different fordifferent radio access technologies (e.g., LTE, LTE-A, LTE-A Pro, NR).For example, communications over a carrier may be organized according toTTIs or slots, each of which may include user data as well as controlinformation or signaling to support decoding the user data. A carriermay also include dedicated acquisition signaling (e.g., synchronizationsignals or system information, etc.) and control signaling thatcoordinates operation for the carrier. In some examples (e.g., in acarrier aggregation configuration), a carrier may also have acquisitionsignaling or control signaling that coordinates operations for othercarriers.

Physical channels may be multiplexed on a carrier according to varioustechniques. A physical control channel and a physical data channel maybe multiplexed on a downlink carrier, for example, using time divisionmultiplexing (TDM) techniques, frequency division multiplexing (FDM)techniques, or hybrid TDM-FDM techniques. In some examples, controlinformation transmitted in a physical control channel may be distributedbetween different control regions in a cascaded manner (e.g., between acommon control region or common search space and one or more UE-specificcontrol regions or UE-specific search spaces).

A carrier may be associated with a particular bandwidth of the radiofrequency spectrum, and in some examples the carrier bandwidth may bereferred to as a “system bandwidth” of the carrier or the wirelesscommunications system 100. For example, the carrier bandwidth may be oneof a number of predetermined bandwidths for carriers of a particularradio access technology (e.g., 1.4, 3, 5, 10, 15, 20, 40, or 80 MHz). Insome examples, each served UE 115 may be configured for operating overportions or all of the carrier bandwidth. In other examples, some UEs115 may be configured for operation using a narrowband protocol typethat is associated with a predefined portion or range (e.g., set ofsubcarriers or RBs) within a carrier (e.g., “in-band” deployment of anarrowband protocol type).

In a system employing MCM techniques, a resource element may consist ofone symbol period (e.g., a duration of one modulation symbol) and onesubcarrier, where the symbol period and subcarrier spacing are inverselyrelated. The number of bits carried by each resource element may dependon the modulation scheme (e.g., the order of the modulation scheme).Thus, the more resource elements that a UE 115 receives and the higherthe order of the modulation scheme, the higher the data rate may be forthe UE 115. In MIMO systems, a wireless communications resource mayrefer to a combination of a radio frequency spectrum resource, a timeresource, and a spatial resource (e.g., spatial layers), and the use ofmultiple spatial layers may further increase the data rate forcommunications with a UE 115.

Devices of the wireless communications system 100 (e.g., base stations105 or UEs 115) may have a hardware configuration that supportscommunications over a particular carrier bandwidth, or may beconfigurable to support communications over one of a set of carrierbandwidths. In some examples, the wireless communications system 100 mayinclude base stations 105 and/or UEs 115 that support simultaneouscommunications via carriers associated with more than one differentcarrier bandwidth. The wireless communications system 100 may supportcommunication with a UE 115 on multiple cells or carriers, a featurewhich may be referred to as carrier aggregation or multi-carrieroperation. A UE 115 may be configured with multiple downlink componentcarriers and one or more uplink component carriers according to acarrier aggregation configuration. Carrier aggregation may be used withboth FDD and TDD component carriers.

In some cases, wireless communications system 100 may utilize enhancedcomponent carriers (eCCs). An eCC may be characterized by one or morefeatures including wider carrier or frequency channel bandwidth, shortersymbol duration, shorter TTI duration, or modified control channelconfiguration. In some cases, an eCC may be associated with a carrieraggregation configuration or a dual connectivity configuration (e.g.,when multiple serving cells have a suboptimal or non-ideal backhaullink). An eCC may also be configured for use in unlicensed spectrum orshared spectrum (e.g., where more than one operator is allowed to usethe spectrum). An eCC characterized by wide carrier bandwidth mayinclude one or more segments that may be utilized by UEs 115 that arenot capable of monitoring the whole carrier bandwidth or are otherwiseconfigured to use a limited carrier bandwidth (e.g., to conserve power).

In some cases, an eCC may utilize a different symbol duration than othercomponent carriers, which may include use of a reduced symbol durationas compared with symbol durations of the other component carriers. Ashorter symbol duration may be associated with increased spacing betweenadjacent subcarriers. A device, such as a UE 115 or base station 105,utilizing eCCs may transmit wideband signals (e.g., according tofrequency channel or carrier bandwidths of 20, 40, 60, 80 MHz, etc.) atreduced symbol durations (e.g., 16.67 microseconds). A TTI in eCC mayconsist of one or multiple symbol periods. In some cases, the TTIduration (that is, the number of symbol periods in a TTI) may bevariable. The wireless communications system 100 may be an NR systemthat may utilize any combination of licensed, shared, and unlicensedspectrum bands, among others. The flexibility of eCC symbol duration andsubcarrier spacing may allow for the use of eCC across multiplespectrums. In some examples, NR shared spectrum may increase spectrumutilization and spectral efficiency, specifically through dynamicvertical (e.g., across the frequency domain) and horizontal (e.g.,across the time domain) sharing of resources.

FIG. 2 illustrates an example of a wireless communications system 200that supports preamble transmission configuration in accordance withaspects of the present disclosure. The wireless communications system200 may include a base station 105-a and a UE 115-a, which may beexamples of the corresponding devices described with reference toFIG. 1. The wireless communications system 200 may also implementaspects of the wireless communications system 100, such as the basestation 105-a and the UE 115-a supporting multiple different radioaccess technologies including licensed and unlicensed radio frequencyspectrum bands. For example, the base station 105-a and the UE 115-a maysupport 4G systems such as LTE systems, LTE-A systems, and 5G systems.The base station 105-a and the UE 115-a may additionally, oralternatively, support WLAN, such as Wi-Fi (i.e., IEEE 802.11).Accordingly, the base station 105-a and the UE 115-a may be capable ofsupporting at least one or a combination of the different radio accesstechnologies.

Although supporting multiple different radio access technologies maybenefit the base station 105-a and the UE 115-a, for example, in termsof efficiency and latency, there may be an effect on the wirelesscommunications system 200 performance. For example, when either or boththe base station 105-a and the UE 115-a operate according to a firstradio access technology and have the capability to alternatively operateaccording to a second radio access technology, there may be possibleinterference in the wireless communications system 200. Alternatively,the UE 115-a may operate according to a first radio access technologyand impact (e.g., interference) performance on other UEs (not shown)operating according to a second radio access technology. To mitigateinterference-related issues and other issues in the wirelesscommunications system 200, a preamble transmission 210 may be appendedto an uplink transmission 215 to support coexistence between multipledifferent radio access technologies in the wireless communicationssystem 200.

By way of example, the UE 115-a may operate according to 4G, 5G radioaccess technologies without supporting Wi-Fi radio access technologies.In this example, the UE 115-a may be capable of transmitting a Wi-Fipreamble without actually supporting Wi-Fi radio access technologies.Therefore, the UE 115-a supporting 4G, 5G radio access technologies mayappend a Wi-Fi preamble to NR-U communications. As a result, the UE115-a may support coexistence between multiple different radio accesstechnologies. For example, the UE 115-a may enable a fair channelcontention for other UEs (e.g., Wi-Fi devices) attempting to coexistwith UEs (e.g., 4G, 5G devices) on a same channel in the wirelesscommunications system 200. While preamble transmissions from the basestation 105-a have little to no impact on the wireless communicationssystem 200 performance, preamble transmissions from the UE 115-a maypose certain challenges and have an undesirable impact (e.g.,interference, latency) in the wireless communications system 200, asoutlined below.

First, a Wi-Fi preamble may signal that the UE 115-a will begin anuplink transmission before other UEs (not shown in the wirelesscommunications system 200). These other UEs (not shown in the wirelesscommunications system 200) may not transmit a preamble transmission ormay transmit a shorter preamble transmission compared to the UE 115-a,for example, related to same time and frequency resources for a physicaluplink shared channel (PUSCH). As a result, the Wi-Fi preambletransmission from the UE 115-a may block uplink transmissions from otherUEs that my not use preamble transmissions. In addition, a Wi-Fipreamble transmission from the UE 115-a may cause interference to otherUEs, that are transmitting in a previous resource (e.g., mini-slot,slot) than the one on which the UE 115-a is scheduled, when the basestation 105-a (e.g., network scheduler) is unaware of the Wi-Fi preambletransmission from the UE 115-a.

Second, in some examples, if other UEs in addition to the UE 115-atransmit a Wi-Fi preamble transmission (e.g., due to FDM scheduling ofUEs) then the base station 105-a (or an access point (AP) in a WLAN) maybe unable to decode the Wi-Fi preamble transmission. An example Wi-Fipreamble may include a legacy preamble portion and a non-legacy preambleportion. The legacy preamble portion may include a set of fields, whichmay include, for example, an L-STF field, an L-LTF field, and L-SIGfield. The L-STF field and the L-LTF field may be common to all UEs,while the L-SIG field, VHT-SIG-A field, HE-SIG-A field, etc., mayinclude UE specific information. Thereby, channel estimation output fromthe L-LTF field may be impractical for the base station 105-a (or an APin a WLAN) for decoding the L-SIG field, as a result rendering the Wi-Fipreamble transmission from the UEs (including UE 115-a) useless.

The non-legacy preamble portion may be formatted as a very highthroughput (VHT) preamble in accordance with the IEEE 802.11ac amendmentto the IEEE 802.11 standard. Alternatively, the non-legacy preambleportion may be formatted as a high efficiency (HE) frame in accordancewith the IEEE 802.11ax amendment to the IEEE 802.11 standard. Thenon-legacy preamble portion may include a set of fields, one which mayinclude a VHT signaling field (VHT-SIG-A) or an HE signaling field(HE-SIG-A). Both may provide coexistence information to other UEs thatare nearby (not shown) the UE 115-a.

The Wi-Fi preamble (e.g., 802.11ac/ax preambles) may include certainfields that may further support coexistence in the wirelesscommunications system 200. For example, one field in the Wi-Fi preamblemay include bandwidth information (e.g., 20 MHz, 40 MHz, 80 MHz), whichmay be useful when the UE 115-a transmits on more than one sub-bandsimultaneously. However, if the UE 115-a uses a combination notsupported by the 802.11ac/ax preambles, supporting coexistence may bechallenging or unfeasible. Another example field may be an RL-SIG field,which may be a repetition of an L-SIG field, providing added coverageand enhanced decoding of the L-SIG field. This may be useful to silencehidden nodes (e.g., UEs (not shown)) near the base station 105-a thatmay interfere with uplink transmission reception at the base station105-a. While the RL-SIG field may provide robust decoding for the L-SIGfield, because the L-SIG field has a single parity bit, there may beoccasions where the L-SIG field is falsely decoded. To improve the useof a Wi-Fi preamble, the UE 115-a may configure or use a set of reservedbits to indicate a device type of the UE 115-a to other UEs (not shown).For example, the set of reserved bits may indicate that the preamblewaveform was transmitted by an NR-U device.

Third, in some examples, either or both the base station 105-a and theUE 115-a may apply a power control scheme to an NR-U preamble. Applyinga power control scheme to a Wi-Fi preamble, however, may have adverseeffects to benefits of using Wi-Fi preambles. Nevertheless, if no powercontrol scheme is applied to the Wi-Fi preamble, then the UE 115-a mayhave to vary its transmit power, for example, between Wi-Fi preambletransmissions (e.g., when operating according to Wi-Fi radio accesstechnology) and PUSCH transmissions (e.g., when operating according to4G, 5G radio access technologies). Fourth, the UE 115-a may have torefrain from transmitting a Wi-Fi preamble during a transmissionopportunity (TxOP) of the base station 105-a. As a result, the UE 115-amay have to be aware of TxOP for the Wi-Fi preamble transmission.

To alleviate the certain challenges outlined above, the base station105-a may configure the UE 115-a with a preamble configuration. In someexamples, the base station 105-a may configure whether or not the UE115-a can transmit the preamble transmission 210. If the UE 115-a isconfigured to transmit the preamble transmission 210, the UE 115-a maybe configured to indicate the format of the preamble transmission 210(e.g., 802.11a/ac/ax preambles), which may also be band-specific (e.g.,802.11a preamble in 5 GHz band, 802.11ax preamble in 6 GHz band).Additionally, the base station 105-a may configure the UE 115-a withscheduling information (e.g., time and frequency resources related tothe preamble transmission 210). The base station 105-a may provide thescheduling information via a dynamic downlink control information-basedindication, or via uplink channel configuration, etc. In some examples,the scheduling information may be rule-based. For example, the UE 115-amay transmit the preamble transmission 210 to the base station 105-abased on the preamble transmission 210 being scheduled on a fullbandwidth or a partial bandwidth. Additionally, or alternatively, the UE115-a may transmit the preamble transmission 210 to the base station105-a outside the TxOP of the base station 105-a.

In some examples, the base station 105-a may determine a length (e.g.,duration) for the preamble transmission 210. The base station 105-a mayindicate this to the UE 115-a via separate signaling. For example, thissignaling may occur separate from UE scheduled time to avoid singlefrequency network (SFN) effects. The base station 105-a may alsodetermine and transmit an indication of whether a transmit power settingand a beamforming matrix configured for PUSCH applies to Wi-Fipreambles. For example, when using multiple antennas, Wi-Fi preamblesmay be transmitted according to a cyclic delay diversity (CDD) oraccording to a beamformed manner. Lastly, the base station 105-a maydetermine an energy detection threshold for the UE 115-a to use forchannel access. For example, for an uplink transmission, the energydetection threshold may be −62 dBm with a Wi-Fi preamble or −72 dBmwithout a Wi-Fi preamble.

Accordingly, the techniques described herein may provide improvements inpreamble transmission configuration. Furthermore, the techniquesdescribed herein may provide benefits and enhancements to the operationof the UE 115-a. For example, by providing a preamble configuration tothe UE 115-a, the operational characteristics, such as powerconsumption, processor utilization, and memory usage of the UE 115-a maybe reduced. The techniques described herein may also provide efficiencyto the UE 115-a by reducing latency associated with processes related towireless communications, and more specifically to preamble transmissionsappended to uplink transmissions.

FIG. 3 illustrates an example of a process flow 300 that supportspreamble transmission configuration in accordance with aspects of thepresent disclosure. The process flow 300 may include a base station105-b and a UE 115-b, which may be examples of the corresponding devicesdescribed with reference to FIGS. 1 and 2. In some examples, the processflow 300 may implement aspects of wireless communications systems 100and 200. For example, the base station 105-b or the UE 115-b, or bothmay support preamble transmission configuration to mitigatecoexistence-related challenges.

In the following description of the process flow 300, the operationsbetween the base station 105-b and the UE 115-b may be transmitted in adifferent order than the exemplary order shown, or the operationsperformed by the base station 105-b and the UE 115-b may be performed indifferent orders or at different times. Certain operations may also beleft out of the process flow 300, or other operations may be added tothe process flow 300.

At 305, the process flow 300 may commence with the base station 105-band the UE 115-b performing a connection procedure (e.g., performing anaccess procedure, a cell acquisition procedure, a random accessprocedure, a radio resource control connection procedure, a radioresource control configuration procedure). In some examples, either orboth the base station 105-b and the UE 115-b may be configured withmultiple antennas, which may be used for directional or beamformedtransmissions.

At 310, the UE 115-b may transmit UE capability to the base station105-b. In some examples, the UE 115-b may transmit UE capability to thebase station 105-b, as part of the connection procedure. The UEcapability may include an indication that the UE 115-b is capable ofappending a preamble waveform to an uplink transmission to the basestation 105-b. The UE 115-b may also provide additional UEcapability-related information. In some examples, the UE 115-b mayprovide an indication of a version of the preamble waveform or anindication that the UE 115-b dynamically selects a version of thepreamble waveform from a set of preamble waveforms. For example, the UE115-b may indicate to the base station 105-b that it has the capabilityto transmit a Wi-Fi preamble or a NR-U preamble. Alternatively, the UE115-b may simply provide an indication of a length of the preamblewaveform without indicating the version of the preamble waveform. Inthis case, the base station 105-b may be unaware of what the waveform isand may be simply aware that something will be transmitted. The lengthof the preamble waveform may satisfy a threshold length. For example, alength of a preamble waveform may be no longer than X microseconds (us),where X is a positive value.

At 315, the base station 105-b may determine a preamble configuration.In some examples, as part of the connection procedure and upon receivingthe UE capability, the base station 105-b may determine the preambleconfiguration using the UE capability. The base station 105-b maydetermine whether the UE 115-a is capable of appending a preamblewaveform to an uplink transmission. Based on this determination, thebase station 105-b may include in the preamble configuration anindication that the UE 115-b is permitted to append the preamblewaveform to the uplink transmission. In some examples, the base station105-b may determine a format of the preamble waveform. For example, theUE capability may include a device type of the UE 115-b (e.g., a Wi-Fitype, a NR type, an LTE type). Based on the device type, the basestation 105-b may determine and select a format of the preamble waveform(e.g., a Wi-Fi preamble, a NR-U preamble). In accordance with thisdetermination, the base station 105-b may include in the preambleconfiguration an indication of a format of the preamble waveform.

The base station 105-b may also determine timing for transmission of thepreamble waveform. For example, the base station 105-b may determine andinclude in the preamble configuration an indication of a time at whichthe UE 115-b is permitted to transmit the preamble waveform.Additionally, or alternatively, the timing may be based on an uplinkchannel configuration of the UE 115-b or a bandwidth of the uplinktransmission. For example, if the preamble waveform is scheduled on apartial bandwidth, the UE 115-b may be unable to transmit the preamblewaveform. Otherwise, if the preamble waveform is scheduled on a fullbandwidth, the UE 115-b may be able to transmit the preamble waveform.Additionally, or alternatively, the base station 105-b may determine oneor more of its TxOPs. In this example, the timing for transmission ofthe preamble waveform may be based on the TxOPs of the base station105-b. That is, the time at which the UE 115-b is permitted to transmitthe preamble waveform may be based on the transmission opportunity ofthe base station 105-b. The timing may be signaled in a duration fieldvalue (e.g., associated with a field in a preamble) to the UE 115-b.

The base station 105-b may also determine whether (or that) a powersetting and a beamforming matrix configured for an uplink transmissionare applicable to the preamble waveform. Based on this determination,the base station 105-b may include in the preamble configuration anindication that the transmit power setting and the beamforming matrixconfigured for the uplink transmission are applicable to the preamblewaveform. In some examples, the base station 105-b may also determine anenergy detection threshold to use for access to a channel, which thebase station 105-b may include in the preamble configuration anindication of the energy detection threshold. In some examples, theenergy detection threshold may be applicable to the connectionprocedure.

At 320, the base station 105-b may transmit the preamble configurationto the UE 115-b. For example, the base station 105-b may transmit thepreamble configuration to the UE 115-b in a downlink control informationblock, or in a radio resource control message as part of the connectionprocedure. At 325, the UE 115-b may append a preamble to an uplinktransmission in accordance with the preamble configuration. For example,the UE 115-b may receive the preamble configuration and determine, basedon the preamble configuration, whether the UE 115-b is permitted toappend the preamble waveform to the uplink transmission.

The UE 115-b may in some examples receive the preamble configuration anddetermine, based on the preamble configuration, a format of the preamblewaveform. Additionally, or alternatively, the UE 115-b may receive thepreamble configuration and determine, based on the preambleconfiguration, a time at which the UE 115-b is permitted to transmit thepreamble waveform. According to the preamble configuration, the UE 115-bmay generate a preamble waveform and append the preamble waveform to anuplink transmission. At 330, the UE 115-b may transmit an uplinktransmission to the base station 105-b, where the preamble waveform isappended to a beginning of the uplink transmission.

Accordingly, either or both the bases station 105-b and UE 115-b maysupport preamble transmission configuration to support coexistence. Asexplained herein, some benefits of this technique may include enhancedefficiency (e.g., operational characteristics, such as powerconsumption, processor utilization, and memory usage), and improvedsignaling of the preamble transmission configuration with minimalmessaging overhead.

FIG. 4 shows a block diagram 400 of a device 405 that supports preambletransmission configuration in accordance with aspects of the presentdisclosure. The device 405 may be an example of aspects of a UE 115 asdescribed herein. The device 405 may include a receiver 410, a UEcommunications manager 415, and a transmitter 420. The device 405 mayalso include a processor. Each of these components may be incommunication with one another (e.g., via one or more buses).

The receiver 410 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to preambletransmission configuration, etc.). Information may be passed on to othercomponents of the device 405. The receiver 410 may be an example ofaspects of the transceiver 720 described with reference to FIG. 7. Thereceiver 410 may utilize a single antenna or a set of antennas.

The UE communications manager 415 may transmit a first message to a basestation, the first message indicating a UE capability to append apreamble waveform to an uplink transmission to the base station, wherethe preamble waveform is directed at a device (e.g., a device other thanthe base station, the base station, or both), append the preamblewaveform to a second message for transmission to the base station basedon the indicated UE capability, and transmit the second message with theappended preamble waveform. The UE communications manager 415 may alsoreceive from a base station, a preamble configuration for uplinktransmissions, generate, based on the preamble configuration, a preamblewaveform directed to a device, and perform an uplink transmission to thebase station, where the preamble waveform is appended to a beginning ofthe uplink transmission based on the preamble configuration. The UEcommunications manager 415 may be an example of aspects of the UEcommunications manager 710 described herein.

The UE communications manager 415, or its sub-components, may beimplemented in hardware, code (e.g., software or firmware) executed by aprocessor, or any combination thereof. If implemented in code executedby a processor, the functions of the UE communications manager 415, orits sub-components may be executed by a general-purpose processor, adigital signal processor (DSP), an application-specific integratedcircuit (ASIC), a field programmable gate array (FPGA) or otherprogrammable logic device, discrete gate or transistor logic, discretehardware components, or any combination thereof designed to perform thefunctions described in the present disclosure.

The UE communications manager 415, or its sub-components, may bephysically located at various positions, including being distributedsuch that portions of functions are implemented at different physicallocations by one or more physical components. In some examples, the UEcommunications manager 415, or its sub-components, may be a separate anddistinct component in accordance with various aspects of the presentdisclosure. In some examples, the UE communications manager 415, or itssub-components, may be combined with one or more other hardwarecomponents, including but not limited to an input/output (I/O)component, a transceiver, a network server, another computing device,one or more other components described in the present disclosure, or acombination thereof in accordance with various aspects of the presentdisclosure.

The transmitter 420 may transmit signals generated by other componentsof the device 405. In some examples, the transmitter 420 may becollocated with a receiver 410 in a transceiver module. For example, thetransmitter 420 may be an example of aspects of the transceiver 720described with reference to FIG. 7. The transmitter 420 may utilize asingle antenna or a set of antennas.

FIG. 5 shows a block diagram 500 of a device 505 that supports preambletransmission configuration in accordance with aspects of the presentdisclosure. The device 505 may be an example of aspects of a device 405,or a UE 115 as described herein. The device 505 may include a receiver510, a UE communications manager 515, and a transmitter 530. The device505 may also include a processor. Each of these components may be incommunication with one another (e.g., via one or more buses).

The receiver 510 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to preambletransmission configuration, etc.). Information may be passed on to othercomponents of the device 505. The receiver 510 may be an example ofaspects of the transceiver 720 described with reference to FIG. 7. Thereceiver 510 may utilize a single antenna or a set of antennas.

The UE communications manager 515 may be an example of aspects of the UEcommunications manager 415 as described herein. The UE communicationsmanager 515 may include a message component 520 and a preamble component525. The UE communications manager 515 may be an example of aspects ofthe UE communications manager 710 described herein.

The message component 520 may transmit a first message to a basestation, the first message indicating a UE capability to append apreamble waveform to an uplink transmission to the base station, wherethe preamble waveform is directed at a device (e.g., a device other thanthe base station, the base station, or both) and transmit a secondmessage with the appended preamble waveform. The preamble component 525may append the preamble waveform to the second message for transmissionto the base station based on the indicated UE capability. The preamblecomponent 525 may receive from a base station, a preamble configurationfor uplink transmissions and generate, based on the preambleconfiguration, the preamble waveform directed to a device. The messagecomponent 520 may perform an uplink transmission to the base station,where the preamble waveform is appended to a beginning of the uplinktransmission based on the preamble configuration.

The transmitter 530 may transmit signals generated by other componentsof the device 505. In some examples, the transmitter 530 may becollocated with a receiver 510 in a transceiver module. For example, thetransmitter 530 may be an example of aspects of the transceiver 720described with reference to FIG. 7. The transmitter 530 may utilize asingle antenna or a set of antennas.

FIG. 6 shows a block diagram 600 of a UE communications manager 605 thatsupports preamble transmission configuration in accordance with aspectsof the present disclosure. The UE communications manager 605 may be anexample of aspects of a UE communications manager 415, a UEcommunications manager 515, or a UE communications manager 710 describedherein. The UE communications manager 605 may include a messagecomponent 610, a preamble component 615, a preamble version component620, a preamble length component 625, a UE type component 630, a timingcomponent 635, and a channel access component 640. Each of these modulesmay communicate, directly or indirectly, with one another (e.g., via oneor more buses).

The message component 610 may transmit a first message to a basestation, the first message indicating a UE capability to append apreamble waveform to an uplink transmission to the base station, wherethe preamble waveform is directed at a device (e.g., a device other thanthe base station, the base station, or both). The message component 610may perform an uplink transmission to the base station, where thepreamble waveform is appended to a beginning of the uplink transmissionbased on the preamble configuration. In some examples, the messagecomponent 610 may transmit a second message with the appended preamblewaveform.

The preamble component 615 may append the preamble waveform to thesecond message for transmission to the base station based on theindicated UE capability. In some examples, the preamble component 615may receive from a base station, a preamble configuration for uplinktransmissions. In some examples, the preamble component 615 maydetermine, based on the preamble configuration, whether the UE ispermitted to append the preamble waveform to the uplink transmission,where performing the uplink transmission to the base station is based onthe determination. In some examples, the preamble component 615 mayreceive an indication that a transmit power setting and a beamformingmatrix configured for the uplink transmission are applicable to thepreamble waveform, where the uplink transmission includes transmittingthe preamble waveform according to the transmit power setting and usingthe beamforming matrix. The preamble component 615 may generate, basedon the preamble configuration, a preamble waveform directed to a device.In some examples, the preamble component 615 may receive an indicationof a duration field value from the base station, where generating thepreamble waveform includes signaling the indicated duration field valuein the preamble waveform.

The preamble version component 620 may include in the first message anindication of a version of the preamble waveform, where the preamblewaveform appended to the second message is of the indicated version. Insome examples, the preamble version component 620 may include in thefirst message an indication that the UE dynamically selects a version ofthe preamble waveform, where appending the preamble waveform to thesecond message includes dynamically selecting the version of thepreamble waveform. In some examples, the preamble version component 620may determine, based on the preamble configuration, a format of thepreamble waveform, where generating the preamble waveform is based onthe determined format.

The preamble length component 625 may include in the first message anindication of a length of the preamble waveform. The UE type component630 may include in the Wi-Fi preamble an indication of a device type ofthe UE. The timing component 635 may determine, based on the preambleconfiguration, a time at which the UE is permitted to transmit thepreamble waveform, where generating the preamble waveform is based onthe determined time. In some examples, the timing component 635 mayreceive an indication of a transmission opportunity of the base station;where determining the time at which the UE is permitted to transmit thepreamble waveform is further based at least in part on the transmissionopportunity of the base station. The channel access component 640 maydetermine, based on the preamble configuration, an energy detectionthreshold to use for access to a channel. In some examples, the channelaccess component 640 may perform a channel access procedure based on thedetermined energy detection threshold.

FIG. 7 shows a diagram of a system 700 including a device 705 thatsupports preamble transmission configuration in accordance with aspectsof the present disclosure. The device 705 may be an example of orinclude the components of device 405, device 505, or a UE 115 asdescribed herein. The device 705 may include components forbi-directional voice and data communications including components fortransmitting and receiving communications, including a UE communicationsmanager 710, an I/O controller 715, a transceiver 720, an antenna 725,memory 730, and a processor 740. These components may be in electroniccommunication via one or more buses (e.g., bus 745).

The UE communications manager 710 may transmit a first message to a basestation, the first message indicating a UE capability to append apreamble waveform to an uplink transmission to the base station, wherethe preamble waveform is directed at a device (e.g., a device other thanthe base station, the base station, or both), append the preamblewaveform to a second message for transmission to the base station basedon the indicated UE capability, and transmit the second message with theappended preamble waveform. Additionally, or alternatively, the UEcommunications manager 710 may also receive from a base station, apreamble configuration for uplink transmissions, generate, based on thepreamble configuration, a preamble waveform directed to a device, andperform an uplink transmission to the base station, where the preamblewaveform is appended to a beginning of the uplink transmission based onthe preamble configuration.

The I/O controller 715 may manage input and output signals for thedevice 705. The I/O controller 715 may also manage peripherals notintegrated into the device 705. In some cases, the I/O controller 715may represent a physical connection or port to an external peripheral.In some cases, the I/O controller 715 may utilize an operating systemsuch as iOS®, ANDROID®, MS-DOS®, MS-WINDOWS®, OS/2®, UNIX®, LINUX®, oranother known operating system. In other cases, the I/O controller 715may represent or interact with a modem, a keyboard, a mouse, atouchscreen, or a similar device. In some cases, the I/O controller 715may be implemented as part of a processor. In some cases, a user mayinteract with the device 705 via the I/O controller 715 or via hardwarecomponents controlled by the I/O controller 715.

The transceiver 720 may communicate bi-directionally, via one or moreantennas, wired, or wireless links as described herein. For example, thetransceiver 720 may represent a wireless transceiver and may communicatebi-directionally with another wireless transceiver. The transceiver 720may also include a modem to modulate the packets and provide themodulated packets to the antennas for transmission, and to demodulatepackets received from the antennas. In some cases, the device 705 mayinclude a single antenna 725. However, in some cases the device 705 mayhave more than one antenna 725, which may be capable of concurrentlytransmitting or receiving multiple wireless transmissions.

The memory 730 may include random-access memory (RAM) and read-onlymemory (ROM). The memory 730 may store computer-readable,computer-executable code 735 including instructions that, when executed,cause the processor to perform various functions described herein. Insome cases, the memory 730 may contain, among other things, a basicinput/output system (BIOS) which may control basic hardware or softwareoperation such as the interaction with peripheral components or devices.

The code 735 may include instructions to implement aspects of thepresent disclosure, including instructions to support wirelesscommunications. The code 735 may be stored in a non-transitorycomputer-readable medium such as system memory or other type of memory.In some cases, the code 735 may not be directly executable by theprocessor 740 but may cause a computer (e.g., when compiled andexecuted) to perform functions described herein.

The processor 740 may include an intelligent hardware device, (e.g., ageneral-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, anFPGA, a programmable logic device, a discrete gate or transistor logiccomponent, a discrete hardware component, or any combination thereof).In some cases, the processor 740 may be configured to operate a memoryarray using a memory controller. In other cases, a memory controller maybe integrated into the processor 740. The processor 740 may beconfigured to execute computer-readable instructions stored in a memory(e.g., the memory 730) to cause the device 705 to perform variousfunctions (e.g., functions or tasks supporting preamble transmissionconfiguration).

FIG. 8 shows a block diagram 800 of a device 805 that supports preambletransmission configuration in accordance with aspects of the presentdisclosure. The device 805 may be an example of aspects of a basestation 105 as described herein. The device 805 may include a receiver810, a base station communications manager 815, and a transmitter 820.The device 805 may also include a processor. Each of these componentsmay be in communication with one another (e.g., via one or more buses).

The receiver 810 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to preambletransmission configuration, etc.). Information may be passed on to othercomponents of the device 805. The receiver 810 may be an example ofaspects of the transceiver 1120 described with reference to FIG. 11. Thereceiver 810 may utilize a single antenna or a set of antennas.

The base station communications manager 815 may receive a first messagefrom a UE, the first message indicating a UE capability to append apreamble waveform to an uplink transmission to the device 805, where thepreamble waveform is directed at a device (e.g., a device other than thedevice 805 and/or including the device 805) and receive a second messagewith the appended preamble waveform. Additionally, or alternatively, thebase station communications manager 815 may transmit to a UE, a preambleconfiguration including an indication to append a preamble waveform toan uplink transmission, where the preamble waveform is directed at adevice other than the device 805, and receive the uplink transmissionfrom the UE, where the preamble waveform is appended to a beginning ofthe uplink transmission based on the preamble configuration. The basestation communications manager 815 may be an example of aspects of thebase station communications manager 1110 described herein.

The base station communications manager 815, or its sub-components, maybe implemented in hardware, code (e.g., software or firmware) executedby a processor, or any combination thereof. If implemented in codeexecuted by a processor, the functions of the base stationcommunications manager 815, or its sub-components may be executed by ageneral-purpose processor, a DSP, an application-specific integratedcircuit (ASIC), a FPGA or other programmable logic device, discrete gateor transistor logic, discrete hardware components, or any combinationthereof designed to perform the functions described in the presentdisclosure.

The base station communications manager 815, or its sub-components, maybe physically located at various positions, including being distributedsuch that portions of functions are implemented at different physicallocations by one or more physical components. In some examples, the basestation communications manager 815, or its sub-components, may be aseparate and distinct component in accordance with various aspects ofthe present disclosure. In some examples, the base stationcommunications manager 815, or its sub-components, may be combined withone or more other hardware components, including but not limited to aninput/output (I/O) component, a transceiver, a network server, anothercomputing device, one or more other components described in the presentdisclosure, or a combination thereof in accordance with various aspectsof the present disclosure.

The transmitter 820 may transmit signals generated by other componentsof the device 805. In some examples, the transmitter 820 may becollocated with a receiver 810 in a transceiver module. For example, thetransmitter 820 may be an example of aspects of the transceiver 1120described with reference to FIG. 11. The transmitter 820 may utilize asingle antenna or a set of antennas.

FIG. 9 shows a block diagram 900 of a device 905 that supports preambletransmission configuration in accordance with aspects of the presentdisclosure. The device 905 may be an example of aspects of a device 805,or a base station 105 as described herein. The device 905 may include areceiver 910, a base station communications manager 915, and atransmitter 930. The device 905 may also include a processor. Each ofthese components may be in communication with one another (e.g., via oneor more buses).

The receiver 910 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to preambletransmission configuration, etc.). Information may be passed on to othercomponents of the device 905. The receiver 910 may be an example ofaspects of the transceiver 1120 described with reference to FIG. 11. Thereceiver 910 may utilize a single antenna or a set of antennas.

The base station communications manager 915 may be an example of aspectsof the base station communications manager 815 as described herein. Thebase station communications manager 915 may include a message component920 and a preamble component 925. The base station communicationsmanager 915 may be an example of aspects of the base stationcommunications manager 1110 described herein.

The message component 920 may receive a first message from a UE, thefirst message indicating a UE capability to append a preamble waveformto an uplink transmission to the device 905, where the preamble waveformis directed at a device other than the device 905, and receive a secondmessage with the appended preamble waveform. The preamble component 925may transmit to a UE, a preamble configuration including an indicationto append a preamble waveform to an uplink transmission, where thepreamble waveform is directed at a device other than the device 905. Themessage component 920 may receive the uplink transmission from the UE,where the preamble waveform is appended to a beginning of the uplinktransmission based on the preamble configuration.

The transmitter 930 may transmit signals generated by other componentsof the device 905. In some examples, the transmitter 930 may becollocated with a receiver 910 in a transceiver module. For example, thetransmitter 930 may be an example of aspects of the transceiver 1120described with reference to FIG. 11. The transmitter 930 may utilize asingle antenna or a set of antennas.

FIG. 10 shows a block diagram 1000 of a base station communicationsmanager 1005 that supports preamble transmission configuration inaccordance with aspects of the present disclosure. The base stationcommunications manager 1005 may be an example of aspects of a basestation communications manager 815, a base station communicationsmanager 915, or a base station communications manager 1110 describedherein. The base station communications manager 1005 may include amessage component 1010, a preamble component 1015, a preamble versioncomponent 1020, a timing component 1025, and a channel access component1030. Each of these modules may communicate, directly or indirectly,with one another (e.g., via one or more buses).

The message component 1010 may receive a first message from a UE, thefirst message indicating a UE capability to append a preamble waveformto an uplink transmission to a base station (e.g., including the basestation communications manager 1005). The preamble waveform may bedirected at a device other than the base station (e.g., including thebase station communications manager 1005). The message component 1010may receive the uplink transmission from the UE, where the preamblewaveform is appended to a beginning of the uplink transmission based ona preamble configuration. In some examples, the message component 1010may receive a second message with the appended preamble waveform.

The preamble component 1015 may transmit to a UE, the preambleconfiguration including an indication to append a preamble waveform tothe uplink transmission. In some examples, the preamble component 1015may include in the preamble configuration an indication that the UE ispermitted to append the preamble waveform to the uplink transmission.The preamble component 1015 may transmit an indication of a durationfield value to the UE. In some examples, the preamble component 1015 maytransmit an indication that a transmit power setting and a beamformingmatrix configured for the uplink transmission are applicable to thepreamble waveform, where the uplink transmission includes receiving thepreamble waveform according to the transmit power setting and using thebeamforming matrix. In some examples, the preamble version component1020 may include in the preamble configuration an indication of a formatof the preamble waveform.

The timing component 1025 may include in the preamble configuration anindication of a time at which the UE is permitted to transmit thepreamble waveform. In some examples, the timing component 1025 maytransmit an indication of a transmission opportunity of the base stationto the UE; where the time at which the UE is permitted to transmit thepreamble waveform is further based at least in part on the transmissionopportunity of the base station (e.g., including the base stationcommunications manager 1005).

The channel access component 1030 may determine, based on the preambleconfiguration, an energy detection threshold to use for access to achannel. In some examples, the channel access component 1030 may performa channel access procedure based on the determined energy detectionthreshold.

FIG. 11 shows a diagram of a system 1100 including a device 1105 thatsupports preamble transmission configuration in accordance with aspectsof the present disclosure. The device 1105 may be an example of orinclude the components of device 805, device 905, or a base station 105as described herein. The device 1105 may include components forbi-directional voice and data communications including components fortransmitting and receiving communications, including a base stationcommunications manager 1110, a network communications manager 1115, atransceiver 1120, an antenna 1125, memory 1130, a processor 1140, and aninter-station communications manager 1145. These components may be inelectronic communication via one or more buses (e.g., bus 1150).

The base station communications manager 1110 may receive a first messagefrom a UE, the first message indicating a UE capability to append apreamble waveform to an uplink transmission to the device 1105, wherethe preamble waveform is directed at a device other than the device1105, and receive a second message with the appended preamble waveform.Additionally, or alternatively, the base station communications manager1110 may transmit to a UE, a preamble configuration including anindication to append a preamble waveform to an uplink transmission,where the preamble waveform is directed at a device other than thedevice 1105, and receive the uplink transmission from the UE, where thepreamble waveform is appended to a beginning of the uplink transmissionbased on the preamble configuration.

The network communications manager 1115 may manage communications withthe core network (e.g., via one or more wired backhaul links). Forexample, the network communications manager 1115 may manage the transferof data communications for client devices, such as one or more UEs 115.

The transceiver 1120 may communicate bi-directionally, via one or moreantennas, wired, or wireless links as described herein. For example, thetransceiver 1120 may represent a wireless transceiver and maycommunicate bi-directionally with another wireless transceiver. Thetransceiver 1120 may also include a modem to modulate the packets andprovide the modulated packets to the antennas for transmission, and todemodulate packets received from the antennas. In some cases, the device1105 may include a single antenna 1125. However, in some cases thedevice 1105 may have more than one antenna 1125, which may be capable ofconcurrently transmitting or receiving multiple wireless transmissions.

The memory 1130 may include RAM, ROM, or a combination thereof. Thememory 1130 may store computer-readable code 1135 including instructionsthat, when executed by a processor (e.g., the processor 1140) cause thedevice to perform various functions described herein. In some cases, thememory 1130 may contain, among other things, a BIOS which may controlbasic hardware or software operation such as the interaction withperipheral components or devices.

The code 1135 may include instructions to implement aspects of thepresent disclosure, including instructions to support wirelesscommunications. The code 1135 may be stored in a non-transitorycomputer-readable medium such as system memory or other type of memory.In some cases, the code 1135 may not be directly executable by theprocessor 1140 but may cause a computer (e.g., when compiled andexecuted) to perform functions described herein.

The processor 1140 may include an intelligent hardware device, (e.g., ageneral-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, anFPGA, a programmable logic device, a discrete gate or transistor logiccomponent, a discrete hardware component, or any combination thereof).In some cases, the processor 1140 may be configured to operate a memoryarray using a memory controller. In some cases, a memory controller maybe integrated into processor 1140. The processor 1140 may be configuredto execute computer-readable instructions stored in a memory (e.g., thememory 1130) to cause the device 1105 to perform various functions(e.g., functions or tasks supporting preamble transmissionconfiguration).

The inter-station communications manager 1145 may manage communicationswith other base station 105, and may include a controller or schedulerfor controlling communications with UEs 115 in cooperation with otherbase stations 105. For example, the inter-station communications manager1145 may coordinate scheduling for transmissions to UEs 115 for variousinterference mitigation techniques such as beamforming or jointtransmission. In some examples, the inter-station communications manager1145 may provide an X2 interface within an LTE/LTE-A wirelesscommunication network technology to provide communication between basestations 105.

FIG. 12 shows a flowchart illustrating a method 1200 that supportspreamble transmission configuration in accordance with aspects of thepresent disclosure. The operations of method 1200 may be implemented bya UE 115 or its components as described herein. For example, theoperations of method 1200 may be performed by a UE communicationsmanager as described with reference to FIGS. 4 through 7. In someexamples, a UE may execute a set of instructions to control thefunctional elements of the UE to perform the functions described herein.Additionally or alternatively, a UE may perform aspects of the functionsdescribed herein using special-purpose hardware.

At 1205, the UE may transmit a first message to a base station, thefirst message indicating a UE capability to append a preamble waveformto an uplink transmission to the base station, where the preamblewaveform is directed at a device (e.g., the base station, a device otherthan the base station, or both). The operations of 1205 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 1205 may be performed by a message component asdescribed with reference to FIGS. 4 through 7.

At 1210, the UE may append the preamble waveform to a second message fortransmission to the base station based on the indicated UE capability.The operations of 1210 may be performed according to the methodsdescribed herein. In some examples, aspects of the operations of 1210may be performed by a preamble component as described with reference toFIGS. 4 through 7.

At 1215, the UE may transmit the second message with the appendedpreamble waveform. The operations of 1215 may be performed according tothe methods described herein. In some examples, aspects of theoperations of 1215 may be performed by a message component as describedwith reference to FIGS. 4 through 7.

FIG. 13 shows a flowchart illustrating a method 1300 that supportspreamble transmission configuration in accordance with aspects of thepresent disclosure. The operations of method 1300 may be implemented bya base station 105 or its components as described herein. For example,the operations of method 1300 may be performed by a base stationcommunications manager as described with reference to FIGS. 8 through11. In some examples, a base station may execute a set of instructionsto control the functional elements of the base station to perform thefunctions described herein. Additionally or alternatively, a basestation may perform aspects of the functions described herein usingspecial-purpose hardware.

At 1305, the base station may receive a first message from a UE, thefirst message indicating a UE capability to append a preamble waveformto an uplink transmission to the base station, where the preamblewaveform is directed at a device. The operations of 1305 may beperformed according to the methods described herein. In some examples,aspects of the operations of 1305 may be performed by a messagecomponent as described with reference to FIGS. 8 through 11.

At 1310, the base station may receive a second message with the appendedpreamble waveform. The operations of 1310 may be performed according tothe methods described herein. In some examples, aspects of theoperations of 1310 may be performed by a message component as describedwith reference to FIGS. 8 through 11.

FIG. 14 shows a flowchart illustrating a method 1400 that supportspreamble transmission configuration in accordance with aspects of thepresent disclosure. The operations of method 1400 may be implemented bya UE 115 or its components as described herein. For example, theoperations of method 1400 may be performed by a UE communicationsmanager as described with reference to FIGS. 4 through 7. In someexamples, a UE may execute a set of instructions to control thefunctional elements of the UE to perform the functions described herein.Additionally or alternatively, a UE may perform aspects of the functionsdescribed herein using special-purpose hardware.

At 1405, the UE may receive from a base station, a preambleconfiguration for uplink transmissions. The operations of 1405 may beperformed according to the methods described herein. In some examples,aspects of the operations of 1405 may be performed by a preamblecomponent as described with reference to FIGS. 4 through 7.

At 1410, the UE may generate, based on the preamble configuration, apreamble waveform directed to a device. The operations of 1410 may beperformed according to the methods described herein. In some examples,aspects of the operations of 1410 may be performed by a preamblecomponent as described with reference to FIGS. 4 through 7.

At 1415, the UE may perform an uplink transmission to the base station,where the preamble waveform is appended to a beginning of the uplinktransmission based on the preamble configuration. The operations of 1415may be performed according to the methods described herein. In someexamples, aspects of the operations of 1415 may be performed by amessage component as described with reference to FIGS. 4 through 7.

FIG. 15 shows a flowchart illustrating a method 1500 that supportspreamble transmission configuration in accordance with aspects of thepresent disclosure. The operations of method 1500 may be implemented bya base station 105 or its components as described herein. For example,the operations of method 1500 may be performed by a base stationcommunications manager as described with reference to FIGS. 8 through11. In some examples, a base station may execute a set of instructionsto control the functional elements of the base station to perform thefunctions described herein. Additionally or alternatively, a basestation may perform aspects of the functions described herein usingspecial-purpose hardware.

At 1505, the base station may transmit to a UE, a preamble configurationincluding an indication to append a preamble waveform to an uplinktransmission, where the preamble waveform is directed at a device. Theoperations of 1505 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1505 may beperformed by a preamble component as described with reference to FIGS. 8through 11.

At 1510, the base station may receive the uplink transmission from theUE, where the preamble waveform is appended to a beginning of the uplinktransmission based on the preamble configuration. The operations of 1510may be performed according to the methods described herein. In someexamples, aspects of the operations of 1510 may be performed by amessage component as described with reference to FIGS. 8 through 11.

It should be noted that the methods described herein describe possibleimplementations, and that the operations and the steps may be rearrangedor otherwise modified and that other implementations are possible.Further, aspects from two or more of the methods may be combined.

Techniques described herein may be used for various wirelesscommunications systems such as code division multiple access (CDMA),time division multiple access (TDMA), frequency division multiple access(FDMA), orthogonal frequency division multiple access (OFDMA), singlecarrier frequency division multiple access (SC-FDMA), and other systems.A CDMA system may implement a radio technology such as CDMA2000,Universal Terrestrial Radio Access (UTRA), etc. CDMA2000 covers IS-2000,IS-95, and IS-856 standards. IS-2000 Releases may be commonly referredto as CDMA2000 1×, 1×, etc. IS-856 (TIA-856) is commonly referred to asCDMA2000 1×EV-DO, High Rate Packet Data (HRPD), etc. UTRA includesWideband CDMA (WCDMA) and other variants of CDMA. A TDMA system mayimplement a radio technology such as Global System for MobileCommunications (GSM).

An OFDMA system may implement a radio technology such as Ultra MobileBroadband (UMB), Evolved UTRA (E-UTRA), Institute of Electrical andElectronics Engineers (IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE802.20, Flash-OFDM, etc. UTRA and E-UTRA are part of Universal MobileTelecommunications System (UMTS). LTE, LTE-A, and LTE-A Pro are releasesof UMTS that use E-UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A, LTE-A Pro, NR,and GSM are described in documents from the organization named “3rdGeneration Partnership Project” (3GPP). CDMA2000 and UMB are describedin documents from an organization named “3rd Generation PartnershipProject 2” (3GPP2). The techniques described herein may be used for thesystems and radio technologies mentioned herein as well as other systemsand radio technologies. While aspects of an LTE, LTE-A, LTE-A Pro, or NRsystem may be described for purposes of example, and LTE, LTE-A, LTE-APro, or NR terminology may be used in much of the description, thetechniques described herein are applicable beyond LTE, LTE-A, LTE-A Pro,or NR applications.

A macro cell generally covers a relatively large geographic area (e.g.,several kilometers in radius) and may allow unrestricted access by UEswith service subscriptions with the network provider. A small cell maybe associated with a lower-powered base station, as compared with amacro cell, and a small cell may operate in the same or different (e.g.,licensed, unlicensed, etc.) frequency bands as macro cells. Small cellsmay include pico cells, femto cells, and micro cells according tovarious examples. A pico cell, for example, may cover a small geographicarea and may allow unrestricted access by UEs with service subscriptionswith the network provider. A femto cell may also cover a smallgeographic area (e.g., a home) and may provide restricted access by UEshaving an association with the femto cell (e.g., UEs in a closedsubscriber group (CSG), UEs for users in the home, and the like). An eNBfor a macro cell may be referred to as a macro eNB. An eNB for a smallcell may be referred to as a small cell eNB, a pico eNB, a femto eNB, ora home eNB. An eNB may support one or multiple (e.g., two, three, four,and the like) cells, and may also support communications using one ormultiple component carriers.

The wireless communications systems described herein may supportsynchronous or asynchronous operation. For synchronous operation, thebase stations may have similar frame timing, and transmissions fromdifferent base stations may be approximately aligned in time. Forasynchronous operation, the base stations may have different frametiming, and transmissions from different base stations may not bealigned in time. The techniques described herein may be used for eithersynchronous or asynchronous operations.

Information and signals described herein may be represented using any ofa variety of different technologies and techniques. For example, data,instructions, commands, information, signals, bits, symbols, and chipsthat may be referenced throughout the description may be represented byvoltages, currents, electromagnetic waves, magnetic fields or particles,optical fields or particles, or any combination thereof.

The various illustrative blocks and modules described in connection withthe disclosure herein may be implemented or performed with ageneral-purpose processor, a DSP, an ASIC, an FPGA, or otherprogrammable logic device, discrete gate or transistor logic, discretehardware components, or any combination thereof designed to perform thefunctions described herein. A general-purpose processor may be amicroprocessor, but in the alternative, the processor may be anyconventional processor, controller, microcontroller, or state machine. Aprocessor may also be implemented as a combination of computing devices(e.g., a combination of a DSP and a microprocessor, multiplemicroprocessors, one or more microprocessors in conjunction with a DSPcore, or any other such configuration).

The functions described herein may be implemented in hardware, softwareexecuted by a processor, firmware, or any combination thereof. Ifimplemented in software executed by a processor, the functions may bestored on or transmitted over as one or more instructions or code on acomputer-readable medium. Other examples and implementations are withinthe scope of the disclosure and appended claims. For example, due to thenature of software, functions described herein can be implemented usingsoftware executed by a processor, hardware, firmware, hardwiring, orcombinations of any of these. Features implementing functions may alsobe physically located at various positions, including being distributedsuch that portions of functions are implemented at different physicallocations.

Computer-readable media includes both non-transitory computer storagemedia and communication media including any medium that facilitatestransfer of a computer program from one place to another. Anon-transitory storage medium may be any available medium that can beaccessed by a general purpose or special purpose computer. By way ofexample, and not limitation, non-transitory computer-readable media mayinclude RAM, ROM, electrically erasable programmable ROM (EEPROM), flashmemory, compact disk (CD) ROM or other optical disk storage, magneticdisk storage or other magnetic storage devices, or any othernon-transitory medium that can be used to carry or store desired programcode means in the form of instructions or data structures and that canbe accessed by a general-purpose or special-purpose computer, or ageneral-purpose or special-purpose processor. Also, any connection isproperly termed a computer-readable medium. For example, if the softwareis transmitted from a website, server, or other remote source using acoaxial cable, fiber optic cable, twisted pair, digital subscriber line(DSL), or wireless technologies such as infrared, radio, and microwave,then the coaxial cable, fiber optic cable, twisted pair, DSL, orwireless technologies such as infrared, radio, and microwave areincluded in the definition of medium. Disk and disc, as used herein,include CD, laser disc, optical disc, digital versatile disc (DVD),floppy disk and Blu-ray disc where disks usually reproduce datamagnetically, while discs reproduce data optically with lasers.Combinations of the above are also included within the scope ofcomputer-readable media.

As used herein, including in the claims, “or” as used in a list of items(e.g., a list of items prefaced by a phrase such as “at least one of” or“one or more of”) indicates an inclusive list such that, for example, alist of at least one of A, B, or C means A or B or C or AB or AC or BCor ABC (i.e., A and B and C). Also, as used herein, the phrase “basedon” shall not be construed as a reference to a closed set of conditions.For example, an exemplary step that is described as “based on conditionA” may be based on both a condition A and a condition B withoutdeparting from the scope of the present disclosure. In other words, asused herein, the phrase “based on” shall be construed in the same manneras the phrase “based at least in part on.”

In the appended figures, similar components or features may have thesame reference label. Further, various components of the same type maybe distinguished by following the reference label by a dash and a secondlabel that distinguishes among the similar components. If just the firstreference label is used in the specification, the description isapplicable to any one of the similar components having the same firstreference label irrespective of the second reference label, or othersubsequent reference label.

The description set forth herein, in connection with the appendeddrawings, describes example configurations and does not represent allthe examples that may be implemented or that are within the scope of theclaims. The term “exemplary” used herein means “serving as an example,instance, or illustration,” and not “preferred” or “advantageous overother examples.” The detailed description includes specific details forthe purpose of providing an understanding of the described techniques.These techniques, however, may be practiced without these specificdetails. In some instances, well-known structures and devices are shownin block diagram form in order to avoid obscuring the concepts of thedescribed examples.

The description herein is provided to enable a person skilled in the artto make or use the disclosure. Various modifications to the disclosurewill be readily apparent to those skilled in the art, and the genericprinciples defined herein may be applied to other variations withoutdeparting from the scope of the disclosure. Thus, the disclosure is notlimited to the examples and designs described herein, but is to beaccorded the broadest scope consistent with the principles and novelfeatures disclosed herein.

What is claimed is:
 1. A method for wireless communications at a userequipment (UE), comprising: transmitting a first message to a basestation, the first message indicating a UE capability to append apreamble waveform to an uplink transmission to the base station, whereinthe preamble waveform is associated with a first radio access technologyand the uplink transmission is associated with a second radio accesstechnology; appending the preamble waveform to the uplink transmissionto the base station based at least in part on the indicated UEcapability; and transmitting, to the base station, the uplinktransmission with the appended preamble waveform.
 2. The method of claim1, further comprising: including in the first message an indication of aversion of the preamble waveform, wherein the preamble waveform appendedto the uplink transmission is of the indicated version.
 3. The method ofclaim 1, further comprising: including in the first message anindication that the UE dynamically selects a version of the preamblewaveform, wherein appending the preamble waveform to the uplinktransmission comprises dynamically selecting the version of the preamblewaveform.
 4. The method of claim 1, further comprising: including in thefirst message an indication of a length of the preamble waveform.
 5. Themethod of claim 1, wherein the preamble waveform comprises a Wi-Fipreamble or a new radio unlicensed (NR-U) preamble.
 6. The method ofclaim 5, further comprising: including in the Wi-Fi preamble anindication of a device type of the UE.
 7. A method for wirelesscommunications at a base station, comprising: receiving a first messagefrom a user equipment (UE), the first message indicating a UE capabilityto append a preamble waveform to an uplink transmission to the basestation, wherein the preamble waveform is associated with a first radioaccess technology and the uplink transmission is associated with asecond radio access technology; and receiving the uplink transmissionwith the appended preamble waveform.
 8. The method of claim 7, whereinthe first message comprises an indication of a version of the preamblewaveform, wherein the preamble waveform appended to the uplinktransmission is of the indicated version.
 9. The method of claim 7,wherein the first message comprises an indication that the UEdynamically selects a version of the preamble waveform.
 10. The methodof claim 7, wherein the first message comprises an indication of alength of the preamble waveform.
 11. The method of claim 7, wherein thepreamble waveform comprises a Wi-Fi preamble or a new radio unlicensed(NR-U) preamble.
 12. The method of claim 11, wherein the Wi-Fi preamblecomprises an indication of a device type of the UE.
 13. A method forwireless communications at a user equipment (UE), comprising: receivingfrom a base station, a preamble configuration for an uplink transmissionassociated with a second radio access technology; generating, based atleast in part on the preamble configuration, a preamble waveformassociated with a first radio access technology; and performing theuplink transmission to the base station, wherein the preamble waveformis appended to a beginning of the uplink transmission based at least inpart on the preamble configuration.
 14. The method of claim 13, furthercomprising: determining, based at least in part on the preambleconfiguration, whether the UE is permitted to append the preamblewaveform to the uplink transmission, wherein performing the uplinktransmission to the base station is based at least in part on thedetermination.
 15. The method of claim 13, further comprising:determining, based at least in part on the preamble configuration, aformat of the preamble waveform, wherein generating the preamblewaveform is based at least in part on the determined format.
 16. Themethod of claim 15, wherein determining the format of the preamblewaveform is further based at least in part on a band of the uplinktransmission.
 17. The method of claim 13, further comprising:determining, based at least in part on the preamble configuration, atime at which the UE is permitted to transmit the preamble waveform,wherein generating the preamble waveform is based at least in part onthe determined time.
 18. The method of claim 17, wherein the preambleconfiguration is received in a downlink control information blockcomprising an indication of the time at which the UE is permitted totransmit the preamble waveform.
 19. The method of claim 17, whereindetermining the time at which the UE is permitted to transmit thepreamble waveform is further based at least in part on one or more of:an uplink channel configuration of the UE or a bandwidth of the uplinktransmission.
 20. The method of claim 17, further comprising: receivingan indication of a transmission opportunity of the base station, whereindetermining the time at which the UE is permitted to transmit thepreamble waveform is further based at least in part on the transmissionopportunity of the base station.
 21. The method of claim 13, furthercomprising: receiving an indication of a duration field value from thebase station, wherein generating the preamble waveform comprisessignaling the indicated duration field value in the preamble waveform.22. A method for wireless communications at a base station, comprising:transmitting to a user equipment (UE), a preamble configurationcomprising an indication to append a preamble waveform to an uplinktransmission, wherein the preamble waveform is associated with a firstradio access technology and the uplink transmission is associated with asecond radio access technology; and receiving the uplink transmissionfrom the UE, wherein the preamble waveform is appended to a beginning ofthe uplink transmission based at least in part on the preambleconfiguration.
 23. The method of claim 22, further comprising: includingin the preamble configuration an indication that the UE is permitted toappend the preamble waveform to the uplink transmission.
 24. The methodof claim 22, further comprising: including in the preamble configurationan indication of a format of the preamble waveform.
 25. The method ofclaim 24, wherein the format of the preamble waveform is further basedat least in part on a band of the uplink transmission.
 26. The method ofclaim 22, further comprising: including in the preamble configuration anindication of a time at which the UE is permitted to transmit thepreamble waveform.
 27. The method of claim 26, wherein the preambleconfiguration is transmitted in a downlink control information blockcomprising an indication of the time at which the UE is permitted totransmit the preamble waveform.
 28. The method of claim 26, wherein thetime at which the UE is permitted to transmit the preamble waveform isfurther based at least in part on one or more of: an uplink channelconfiguration of the UE or a bandwidth of the uplink transmission. 29.The method of claim 26, further comprising: transmitting an indicationof a transmission opportunity of the base station to the UE, wherein thetime at which the UE is permitted to transmit the preamble waveform isfurther based at least in part on the transmission opportunity of thebase station.
 30. The method of claim 22, further comprising:transmitting an indication of a duration field value to the UE.